Handle parentheses around computed projections

src/webserver/database/sql.rs

@@ -433,6 +433,21 @@ mod tests {
         assert!(!query.sql.contains("sqlpage."));
     }
 
+    #[test]
+    fn parentheses_keep_nested_call_per_row() {
+        let FileStatement::Query(Query {
+            body: QueryBody::Database(query),
+            ..
+        }) = one("select (sqlpage.url_encode(value)) as encoded from t")
+        else {
+            panic!("expected database query");
+        };
+        assert!(query.bindings.is_empty());
+        assert_eq!(query.row_input_json.len(), 1);
+        assert_eq!(query.computed_columns.len(), 1);
+        assert!(!query.sql.contains("sqlpage."));
+    }
+
     #[test]
     fn row_value_cannot_cross_database_only_parent() {
         let FileStatement::Error(error) = one("select upper(sqlpage.url_encode(value)) from t")

src/webserver/database/sql/rewrite.rs

@@ -476,6 +476,7 @@ fn can_build_standalone(expression: &SqlExpr) -> anyhow::Result<bool> {
             op: BinaryOperator::StringConcat,
             right,
         } => Ok(can_build_standalone(left)? && can_build_standalone(right)?),
+        SqlExpr::Nested(expression) => can_build_standalone(expression),
         _ => Ok(false),
     }
 }
@@ -522,6 +523,14 @@ impl QueryRewriter<'_> {
                     })),
                 }
             }
+            SqlExpr::Nested(expression) => match self.rewrite_projection(*expression)? {
+                RewrittenProjection::Database(expression) => Ok(RewrittenProjection::Database(
+                    SqlExpr::Nested(Box::new(expression)),
+                )),
+                RewrittenProjection::PerRow(expression) => {
+                    Ok(RewrittenProjection::PerRow(expression))
+                }
+            },
             mut expression => {
                 self.rewrite_database_expression(&mut expression)?;
                 Ok(RewrittenProjection::Database(expression))
@@ -814,6 +823,7 @@ fn build_sqlpage_expr<Environment: ExprEnvironment>(
                 .database_type
                 .concat_operator_null_behavior(),
         }),
+        SqlExpr::Nested(expression) => build_sqlpage_expr::<Environment>(rewriter, *expression),
         expression => Environment::use_database_expr(rewriter, expression),
     }
 }

tests/sql_test_files/data/delayed_function_parentheses.sql

@@ -0,0 +1,6 @@
+select
+    (sqlpage.url_encode(subquery.space)) as actual,
+    '%20' as expected
+from (
+    select ' ' as space
+) AS subquery;